Narrative:

Passenger alerted flight attendant to oil leak in right engine. Flight attendant notified flight deck crew and captain left flight deck to inspect. Captain returned and asked me to inspect so we could discuss options (wanted opinion on severity, loss rate, fuel or oil, etc). We jointly decided it was oil leak and warranted a diversion to lake charles. I informed ATC we were currently executing a 180 degree turn direct to lake charles ATC asked if we were needing special assistance. I told him no, but would like to request priority handling. He said we had it. About 30 seconds later, oil pressure began to fluctuate. Power was reduced to nn less than 75 percent for the duration of flight per company procedures. We got an aural oil pressure warning at 100 ft AGL. Elected to continue approach (reduced power to flight idle). Secured engine on landing. Oil pressure warning was intermittent due to oil pressure fluctuations. Problem was determined by maintenance to be a broken o-ring that fit on the starter-generator shaft. Only thing I would have done different would have been to include ATC in the loop. I'm sure he would have better understood the reason for the priority handling had he been told of the oil pressure problem. Should have mentioned that we elected not to shut engine down because source of oil leak was through starter-generator cowling vent and no smoke (suggesting no fire hazard). Flight attendant was to inform us of any changes.

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Original NASA ASRS Text

Title: PAX NOTIFIES FLT ATTENDANT OF ENG OIL LEAK. AFTER INSPECTION FLC REQUESTS PRIORITY HANDLING AND DIVERTS TO PRECAUTIONARY LNDG.

Narrative: PAX ALERTED FLT ATTENDANT TO OIL LEAK IN R ENG. FLT ATTENDANT NOTIFIED FLT DECK CREW AND CAPT LEFT FLT DECK TO INSPECT. CAPT RETURNED AND ASKED ME TO INSPECT SO WE COULD DISCUSS OPTIONS (WANTED OPINION ON SEVERITY, LOSS RATE, FUEL OR OIL, ETC). WE JOINTLY DECIDED IT WAS OIL LEAK AND WARRANTED A DIVERSION TO LAKE CHARLES. I INFORMED ATC WE WERE CURRENTLY EXECUTING A 180 DEG TURN DIRECT TO LAKE CHARLES ATC ASKED IF WE WERE NEEDING SPECIAL ASSISTANCE. I TOLD HIM NO, BUT WOULD LIKE TO REQUEST PRIORITY HANDLING. HE SAID WE HAD IT. ABOUT 30 SECONDS LATER, OIL PRESSURE BEGAN TO FLUCTUATE. PWR WAS REDUCED TO NN LESS THAN 75 PERCENT FOR THE DURATION OF FLT PER COMPANY PROCS. WE GOT AN AURAL OIL PRESSURE WARNING AT 100 FT AGL. ELECTED TO CONTINUE APCH (REDUCED PWR TO FLT IDLE). SECURED ENG ON LNDG. OIL PRESSURE WARNING WAS INTERMITTENT DUE TO OIL PRESSURE FLUCTUATIONS. PROBLEM WAS DETERMINED BY MAINT TO BE A BROKEN O-RING THAT FIT ON THE STARTER-GENERATOR SHAFT. ONLY THING I WOULD HAVE DONE DIFFERENT WOULD HAVE BEEN TO INCLUDE ATC IN THE LOOP. I'M SURE HE WOULD HAVE BETTER UNDERSTOOD THE REASON FOR THE PRIORITY HANDLING HAD HE BEEN TOLD OF THE OIL PRESSURE PROBLEM. SHOULD HAVE MENTIONED THAT WE ELECTED NOT TO SHUT ENG DOWN BECAUSE SOURCE OF OIL LEAK WAS THROUGH STARTER-GENERATOR COWLING VENT AND NO SMOKE (SUGGESTING NO FIRE HAZARD). FLT ATTENDANT WAS TO INFORM US OF ANY CHANGES.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.